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Abstract The magnetic signature of a marine vessel is the distortion created by the vessel in the earth’s magnetic field. Magnetic signature has long been exploited by sea magnetic mines to destroy or disable marine vessels. To provide protection against magnetic threats, larger magnetic signature should be avoided. The purpose of this study is to extrapolate the 3D induced magnetic signatures and to analyze the difference between the signature components in two major vessel models. Each of the vessel models has its own geometrical features. Each model has five different scenarios. Signature differences between scenarios from the same model will be compared; thus, the effect of either under- water feature elements or superstructure configurations upon the magnetic signature can be recognized and quantified. The aim of study is to investigate and evaluate the effects on the vessel’s magnetic signature due to the existence of multiple major underwater structural parts, such as propeller shafts, rudders and podded propulsion systems. Similar effects due to different superstructure configurations will be studied as well. Numerical modeling was conducted considering full-scale vessel dimensions and using COMSOL Multiphysics as the finite-element analysis (FEA) modeling software. Measurements on a 1:100 properly scaled and designed physical scale model (PSM) were conducted in a magnetically clean area. To enrich the analysis, both signature components from the numerical evaluation and the experimental measurements were 3D mapped. Both the scaling technique and scaling effect on magnetic signature were investigated. The signature measurements of the scaled- vessel models were performed to verify the numerical models. Both the numerical and experimental results are discussed and shown to be consistent. Although under- recognized, the extrapolated signature components revealed that the studied effects are prominent as the saliency of the 3D mapped signature components increased. Consequently, the studied effects increased the magnetic susceptibility of the vessel for detection or destruction. Finally, this study suggests solutions to reduce the studied effects and gives recommendations for future studies. |